| 摘要 |
PURPOSE:To detect whether a data value is true or false by saving the same data in plural non-volatile RAMs and comparing values of data read out from all non-volatile RAMs with one another at the time of restoration to judge whether data is normal or not. CONSTITUTION:At the time of saving data, a CPU 1 stores data in an address FF02H as well as an address FF12H. At the time of restoring data, the CPU 1 reads out and refers to data in the address FF02H and reads out and refers to data in the address FF12H also. If values of read-out data do not coincide with each other, these values of data are judged to be abnormal. If they coincide with each other, it is judged whether the value of data is within a prescribed range or not, and data is judged to be abnormal if it is not within the prescribed range. If it is within the prescribed range, the normal operation is performed to execute the data processing. |
